1 /* 2 * segment.h - NILFS Segment constructor prototypes and definitions 3 * 4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * Written by Ryusuke Konishi <ryusuke@osrg.net> 21 * 22 */ 23 #ifndef _NILFS_SEGMENT_H 24 #define _NILFS_SEGMENT_H 25 26 #include <linux/types.h> 27 #include <linux/fs.h> 28 #include <linux/buffer_head.h> 29 #include <linux/nilfs2_fs.h> 30 #include "sb.h" 31 32 /** 33 * struct nilfs_recovery_info - Recovery infomation 34 * @ri_need_recovery: Recovery status 35 * @ri_super_root: Block number of the last super root 36 * @ri_ri_cno: Number of the last checkpoint 37 * @ri_lsegs_start: Region for roll-forwarding (start block number) 38 * @ri_lsegs_end: Region for roll-forwarding (end block number) 39 * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start 40 * @ri_used_segments: List of segments to be mark active 41 * @ri_pseg_start: Block number of the last partial segment 42 * @ri_seq: Sequence number on the last partial segment 43 * @ri_segnum: Segment number on the last partial segment 44 * @ri_nextnum: Next segment number on the last partial segment 45 */ 46 struct nilfs_recovery_info { 47 int ri_need_recovery; 48 sector_t ri_super_root; 49 __u64 ri_cno; 50 51 sector_t ri_lsegs_start; 52 sector_t ri_lsegs_end; 53 u64 ri_lsegs_start_seq; 54 struct list_head ri_used_segments; 55 sector_t ri_pseg_start; 56 u64 ri_seq; 57 __u64 ri_segnum; 58 __u64 ri_nextnum; 59 }; 60 61 /* ri_need_recovery */ 62 #define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */ 63 #define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */ 64 65 /** 66 * struct nilfs_cstage - Context of collection stage 67 * @scnt: Stage count 68 * @flags: State flags 69 * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file 70 * @gc_inode_ptr: Pointer on the list of gc-inodes 71 */ 72 struct nilfs_cstage { 73 int scnt; 74 unsigned flags; 75 struct nilfs_inode_info *dirty_file_ptr; 76 struct nilfs_inode_info *gc_inode_ptr; 77 }; 78 79 struct nilfs_segment_buffer; 80 81 struct nilfs_segsum_pointer { 82 struct buffer_head *bh; 83 unsigned offset; /* offset in bytes */ 84 }; 85 86 /** 87 * struct nilfs_sc_info - Segment constructor information 88 * @sc_super: Back pointer to super_block struct 89 * @sc_sbi: Back pointer to nilfs_sb_info struct 90 * @sc_nblk_inc: Block count of current generation 91 * @sc_dirty_files: List of files to be written 92 * @sc_gc_inodes: List of GC inodes having blocks to be written 93 * @sc_cleaning_segments: List of segments to be freed through construction 94 * @sc_copied_buffers: List of copied buffers (buffer heads) to freeze data 95 * @sc_dsync_inode: inode whose data pages are written for a sync operation 96 * @sc_dsync_start: start byte offset of data pages 97 * @sc_dsync_end: end byte offset of data pages (inclusive) 98 * @sc_segbufs: List of segment buffers 99 * @sc_segbuf_nblocks: Number of available blocks in segment buffers. 100 * @sc_curseg: Current segment buffer 101 * @sc_super_root: Pointer to the super root buffer 102 * @sc_stage: Collection stage 103 * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary 104 * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary 105 * @sc_blk_cnt: Block count of a file 106 * @sc_datablk_cnt: Data block count of a file 107 * @sc_nblk_this_inc: Number of blocks included in the current logical segment 108 * @sc_seg_ctime: Creation time 109 * @sc_flags: Internal flags 110 * @sc_state_lock: spinlock for sc_state and so on 111 * @sc_state: Segctord state flags 112 * @sc_flush_request: inode bitmap of metadata files to be flushed 113 * @sc_wait_request: Client request queue 114 * @sc_wait_daemon: Daemon wait queue 115 * @sc_wait_task: Start/end wait queue to control segctord task 116 * @sc_seq_request: Request counter 117 * @sc_seq_done: Completion counter 118 * @sc_sync: Request of explicit sync operation 119 * @sc_interval: Timeout value of background construction 120 * @sc_mjcp_freq: Frequency of creating checkpoints 121 * @sc_lseg_stime: Start time of the latest logical segment 122 * @sc_watermark: Watermark for the number of dirty buffers 123 * @sc_timer: Timer for segctord 124 * @sc_task: current thread of segctord 125 */ 126 struct nilfs_sc_info { 127 struct super_block *sc_super; 128 struct nilfs_sb_info *sc_sbi; 129 130 unsigned long sc_nblk_inc; 131 132 struct list_head sc_dirty_files; 133 struct list_head sc_gc_inodes; 134 struct list_head sc_cleaning_segments; 135 struct list_head sc_copied_buffers; 136 137 struct nilfs_inode_info *sc_dsync_inode; 138 loff_t sc_dsync_start; 139 loff_t sc_dsync_end; 140 141 /* Segment buffers */ 142 struct list_head sc_segbufs; 143 unsigned long sc_segbuf_nblocks; 144 struct nilfs_segment_buffer *sc_curseg; 145 struct buffer_head *sc_super_root; 146 147 struct nilfs_cstage sc_stage; 148 149 struct nilfs_segsum_pointer sc_finfo_ptr; 150 struct nilfs_segsum_pointer sc_binfo_ptr; 151 unsigned long sc_blk_cnt; 152 unsigned long sc_datablk_cnt; 153 unsigned long sc_nblk_this_inc; 154 time_t sc_seg_ctime; 155 156 unsigned long sc_flags; 157 158 spinlock_t sc_state_lock; 159 unsigned long sc_state; 160 unsigned long sc_flush_request; 161 162 wait_queue_head_t sc_wait_request; 163 wait_queue_head_t sc_wait_daemon; 164 wait_queue_head_t sc_wait_task; 165 166 __u32 sc_seq_request; 167 __u32 sc_seq_done; 168 169 int sc_sync; 170 unsigned long sc_interval; 171 unsigned long sc_mjcp_freq; 172 unsigned long sc_lseg_stime; /* in 1/HZ seconds */ 173 unsigned long sc_watermark; 174 175 struct timer_list *sc_timer; 176 struct task_struct *sc_task; 177 }; 178 179 /* sc_flags */ 180 enum { 181 NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */ 182 NILFS_SC_UNCLOSED, /* Logical segment is not closed */ 183 NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */ 184 NILFS_SC_PRIOR_FLUSH, /* Requesting immediate flush without making a 185 checkpoint */ 186 NILFS_SC_HAVE_DELTA, /* Next checkpoint will have update of files 187 other than DAT, cpfile, sufile, or files 188 moved by GC */ 189 }; 190 191 /* sc_state */ 192 #define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */ 193 #define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */ 194 195 /* 196 * Constant parameters 197 */ 198 #define NILFS_SC_CLEANUP_RETRY 3 /* Retry count of construction when 199 destroying segctord */ 200 201 /* 202 * Default values of timeout, in seconds. 203 */ 204 #define NILFS_SC_DEFAULT_TIMEOUT 5 /* Timeout value of dirty blocks. 205 It triggers construction of a 206 logical segment with a super root */ 207 #define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root 208 creation */ 209 210 /* 211 * The default threshold amount of data, in block counts. 212 */ 213 #define NILFS_SC_DEFAULT_WATERMARK 3600 214 215 216 /* segment.c */ 217 extern int nilfs_init_transaction_cache(void); 218 extern void nilfs_destroy_transaction_cache(void); 219 extern void nilfs_relax_pressure_in_lock(struct super_block *); 220 221 extern int nilfs_construct_segment(struct super_block *); 222 extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *, 223 loff_t, loff_t); 224 extern void nilfs_flush_segment(struct super_block *, ino_t); 225 extern int nilfs_clean_segments(struct super_block *, void __user *); 226 227 extern int nilfs_segctor_add_segments_to_be_freed(struct nilfs_sc_info *, 228 __u64 *, size_t); 229 extern void nilfs_segctor_clear_segments_to_be_freed(struct nilfs_sc_info *); 230 231 extern int nilfs_attach_segment_constructor(struct nilfs_sb_info *); 232 extern void nilfs_detach_segment_constructor(struct nilfs_sb_info *); 233 234 /* recovery.c */ 235 extern int nilfs_read_super_root_block(struct super_block *, sector_t, 236 struct buffer_head **, int); 237 extern int nilfs_search_super_root(struct the_nilfs *, struct nilfs_sb_info *, 238 struct nilfs_recovery_info *); 239 extern int nilfs_recover_logical_segments(struct the_nilfs *, 240 struct nilfs_sb_info *, 241 struct nilfs_recovery_info *); 242 243 #endif /* _NILFS_SEGMENT_H */ 244